Today, unmanned aerial vehicles (or “UAVs”) are used increasingly frequently in an ever-growing number of applications, including but not limited to surveillance, law enforcement, military, safety, crop management, inspection or delivery operations. A modern unmanned aerial vehicle is typically an integrated system that includes a number of propellers, motors, communication equipment, imaging devices, power sources and various other components or machines, and may, in some embodiments, be configured to retrieve, transport or deposit payloads of various sizes. Characterized by their comparatively small sizes and high maneuverability, unmanned aerial vehicles may often perform tasks at lower costs and with lower levels of risk to humans than other powered vehicles, e.g., manned aerial vehicles.
Unmanned aerial vehicles include electrical circuits for powering the various propulsion motors, control surfaces, control systems, payload engagement systems and other electrical loads that are provided thereon. Typically, an unmanned aerial vehicle includes a power source, such as a direct current (DC) battery, that provides power to the onboard electrical loads via pairs of positive and negative leads. Such power sources are typically constructed to provide power at or near a nominal voltage level, and may be recharged, for example, by removing the power sources from the unmanned aerial vehicle and connecting charging leads thereto, or by recharging the power sources in place within the unmanned aerial vehicle.
An output voltage of a battery is a function of the state of its charge. As a battery discharges power, the output voltage of the battery naturally falls over time. Where a battery is provided as a power source for one or more propulsion motors of an unmanned aerial vehicle, a reduction in the output voltage of the battery necessarily reduces the amount of thrust that may be generated by the unmanned aerial vehicle. Moreover, many electrical loads aboard an unmanned aerial vehicle, such as propulsion motors, are subject to surges in starting current or other factors which may cause voltage levels aboard the unmanned aerial vehicle to fluctuate to undesirable degrees.